正如你可以看到下面我需要有一个输出显示添加，更改，和删除学生。我认为我已经研究了如何准确地做到这一点，并不断寻找我有什么设置目前在RemovedStudents()中。有人有任何例子，可以帮助我完成这一点的添加，更改和删除学生的方法？我会很感激任何帮助！

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;

namespace OldandNewStudents
{
    class Program
    {
        static void Main(string[] args)
        {
            //Display lists of students
            Console.WriteLine("Here is the list of old students: ");
            ShowStudents(GetStudentsOld());
            Console.WriteLine("Here is the list of new students: ");
            ShowStudents(GetStudentsNew());

            //Show the additions
            Console.WriteLine("Here is the list Additions: ");

            //Show the changes
            Console.WriteLine("Here is the list of Changes: ");

            //Show the removed students
            Console.WriteLine("Here is the list of removed students: ");
            RemovedStudents(GetStudentsNew(), GetStudentsOld());
            Console.ReadLine();
        }

        public static List<Student> GetStudentsOld()
        {
            List<Student> students = new List<Student>();

            students.Add(new Student("111", "Michael", "Tucker", "Junior", 10));
            students.Add(new Student("222", "Svetlana", "Omelchenko", "Senior", 2));
            students.Add(new Student("333", "Michiko", "Osada", "Senior", 7));
            students.Add(new Student("444", "Hugo", "Garcia", "Junior", 16));
            students.Add(new Student("555", "Cesar", "Garcia", "Freshman", 4));
            students.Add(new Student("666", "Fadi", "Fakhouri", "Senior", 72));
            students.Add(new Student("777", "Hanying", "Feng", "Senior", 11));
            students.Add(new Student("888", "Debra", "Garcia", "Junior", 41));
            students.Add(new Student("999", "Terry", "Adams", "Senior", 6));
            students.Add(new Student("211", "Bob", "Stephenson", "Junior", 150));
            return students;
        }

        public static List<Student> GetStudentsNew()
        {
           List<Student> students = new List<Student>();

            students.Add(new Student("111", "Michael", "Tucker", "Junior", 10));
            students.Add(new Student("222", "Svetlana", "Omelchenko", "Senior", 2));
            students.Add(new Student("333", "Michiko", "Osada", "Senior", 7));
            students.Add(new Student("311", "Sven", "Mortensen", "Freshman", 53));
            students.Add(new Student("444", "Hugo", "Garcia", "Freshman", 16));
            students.Add(new Student("555", "Cesar", "Garcia", "Freshman", 4));
            students.Add(new Student("666", "Fadi", "Fakhouri", "Senior", 72));
            students.Add(new Student("777", "Hanying", "Feng", "Senior", 11));
            students.Add(new Student("888", "Debra", "Garcia", "Junior", 41));
            students.Add(new Student("411", "Lance", "Tucker", "Junior", 60));
            students.Add(new Student("999", "Terry", "Adams", "Senior", 6));
            return students;
        }

        public static void ShowStudents(List<Student> stuList)
        {
            Console.WriteLine();

            foreach (Student s in stuList)
            {
                Console.WriteLine(s);
            }
            Console.WriteLine();
        }

        public static void RemovedStudents(List<Student> stuNewList, List<Student> stuOldList)
        {
            List<Student> removedStudents = stuNewList.Except(stuOldList).ToList();
            IEnumerable<Student> differenceQuery = stuNewList.Except(stuOldList);
            foreach (Student s in differenceQuery)
                Console.WriteLine(s);
        }
    }
}

下面是我新更新的RemovedStudents方法：

public static void RemovedStudents(List<Student> stuNewList, List<Student> stuOldList)
    {
        GetStudentsOld().Except(GetStudentsNew());
        foreach (Student s in stuNewList)
            Console.WriteLine("student: {0} {1}", s.FirstName, s.LastName);
    }

下面是学生类，但不允许我编辑它：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace OldandNewStudents
{
public class Student
{
    // Sample Student class
    // Each student has a first name, a last name, a class year, and a rank 
    // that indicates academic ranking in the student body.

    public string ID { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string StudentYear { get; set; }
    public int StudentRank { get; set; }

    public Student(string idNumber, string firstName, string lastName, string studentYear, int studentRank)
    {
        ID = idNumber;
        FirstName = firstName;
        LastName = lastName;
        StudentYear = studentYear;
        StudentRank = studentRank;
    }

    public override string ToString()
    {
        return ID + " " + FirstName + " " + LastName + " " + StudentYear + " " + StudentRank;
    }
}
}

下面是我的NEW加法方法，但我不确定为什么会出现重载错误：

public static List<Student> GetActualNewStudents(List<Student> oldStudents, List<Student> newStudents)
    {
        List<Student> actualNewStudents = new List<Student>();

        foreach (var student in oldStudents) {
            if (oldStudents[student].ID != newStudents[student].ID)
            {
                actualNewStudents.Add(newStudents[student]);
            }
        }

        return actualNewStudents;
    }